Even in pitchblende, polonium is exceedingly rare: 1,000 tons of ore must be treated to yield 40 milligrams of polonium. It has a one-part-in-ten-thousandth-thousandth-thousandth-thousandth-thousandth-thousandth It is found in nature as a byproduct of the radioactive decay of uranium, thorium, and actinium.
Atomic Number: 210